I don't like talking on _______ telephone; I prefer writing _______ letters.
The NBA is _____ organization of professional(职业的) basketball players in the USA. A. a B. an C. the D. /
We used to work in the same office and we _________ have coffee together.
_____ all the inventions have in common is ______ they have succeeded.
The new machine,if _________ properly,will work at least ten years.
—What were you doing when the telephone rang?—I ______ away my books and ______ to bed.